Joint mechanism



y 1932- H. c. LORD 1,856,647

JOINT MECHANISM Original Filed Jan. 21, 1927 r IN VEN TOR.

A TTORNEYS.

Patented May 3, 1932 .l

v UNITED. STATES HUGH 6. LORD, OF ERIE, PENNSYLVANIA .roinr MECHANISM Original application filed January 21, 1927, Serial No. 162,666. Divided and this application filed December 10, 1929.

The present invention is directed to joint mechanisms in which there is a wobble movement of one member relatively to the other which, in the referred joint mechanism, in-

volves an oscil ator movement on more than one axis. It is particularly useful with joints having a comparatively large movement about one axis and a com aratively. small movement about another axis, as for example the joints at the outer ends of the drag link in tie rods of an automobile. This application is a division of application Serial No. 162,666, filed January 21st, 1927 for improvements in joint mechanisms.

A preferred embodiment of the invention is illustrated in the accompanying drawings as follows Fig. 1 shows a plan view of the front axle of an automobile with a steering gear thereon. Fig. 2 an enlarged sectional view of one of the jointson'the line 2-2 in Fig. 3.

Fig. 3 a section on the line 3-3 in Fig. 2. 1 marks an automobile axle, 2 the front wheels, and 3 the king bolts, the front wheels being slightly ofi perpendicular. Knuckles 4 are j ournaled on the king bolts and carry the wheels and are provided with the usual arms 4a. A tie rod 6 extends between the arms and terminates in clevises 7.

Each joint is provided with the clevis 7 and a bolt 8 extending between the arms of the clevis, said bolt having a head 8a and a clamping nut 86. The bolt extends through an inner joint member 9 in theform of a metallic 85 sleeve. A rubber joint member 10 is arranged on the sleeve 9 and within a shell 11. The shell is pressed into sockets 5 in the knuckle arms.

Preferably the rubber is secured to the surfaces of the inner and outer joint members by uniting the engaging surfaces and this can be particularly well accom lished dur-. arm 12 is ing vulcanization. A drag lin secured to one of the knuckles and a drag link 13 extends from this arm to a rock arm 14 Serial No. 413,035.

of the steerin gear, the rock arm being fixed on a she t 15 and swings on the axis of the shaft 15 in the usual manner. At the ends of the drag links there are joints exactly similar to those at the ends of the tie rods, namely having the clevises 7-7, the connecting bolts 8-8, and the rubber joint element pressed into an eye 12a on the drag link arm 12 and 14a onthe steeringgear arm. At the ends of the drag link it will be noted that there is oscillatory movement on the axis of the sleeve 9 of considerable amplitude and in addition thereto there is a swin 'ng movement withan axis across the axis 0 the inner joint member. At the front end of the drag link this cross swinging is due to the raising and lowering of the frame due to the swingmg action and also to the arc of travel at the end of the arm 14. Similarly the joint at the lower end of the arm 14 has an oscile5 latory movement due to the swinging of the v arm on the axis of the sleeve 9 and also a cross movement due to the arc of travel of the end of the arm 12.

The shell 11 is short compared to the diameter of the joint. Consequently if the joint is swung across the axis the movement at the ends of the outer shell is more nearly in line with the axis of the joint member than a radial direction. It will be under 7 stood that this cocking of the shell 11 due to this swinging on this cross axis tends to compress the rubber at opposite ends and diagonally across the rubber. If the shell is comparatively short the radial movement at the ends of the shell is less pronounced than with a shell that is longer as compared to its diameter. It is this stressing of the rubberthat limits the cross swinging of the joint. I prefer, therefore, to have the meeting points a of the ends of the rubber with the shell positioned at less than an an 1c of 45 from a lane indicated at 11-56 in F1 2 and perpendicular to the longitudinal axis o--c with the vertex of the angle at the radial and axial center d of the joint. It will be seen that the 45 line z e is some distance from the meeting points a between the rubber and the shell arid the arc a-f is more nearly axial with a consequent directgompression, and the crosswise flexingiwould, therefore, be reduced. I prefer to ma e the inner member of the joint sli htly longer than the outer member so that t e mass of rubber immediately surrounding the inner member will more nearly approximate the mass of rubber immediately ad acent to the outer shell and I also prefer to have the rubber at the ends extend inwardl from the path of movement of the end 0 the shell under the crosswise swin ing of the joint. As shown the end of the ru her is cupped and this reduces the banking up of the rubber. under-the end of the shell as it is swung crosswise. Further I prefer t6 place the rubber in the joint under initial tension and this may be accomplished by bonding the rubber to the shell and pin duringvulcanization. Upon the cooling of the rubber it shrinks sufliciently to put the rubber of the joint under initial tension. Con-.

sequently as the shell is cocked, or swung crosswise this initial tension at the point where the shell moves toward the inner pin 9 moves some distance in neutralizing the initial tension before compressing the rubber at this oint and thus subjecting it to the-stresses incident to this crosswise movement. With the rubber united with the en-' difference between the pin and shell as to bond area may be eliminated or reduced. This is of great advantage with the rubber under initial tension, as the tension side of the joint then carries a greater proportion of the oad.

With such a structureit is possible with joint mechanisms, such as tie rods, to accom-' plish the compound movement of the joints with a single joint, thus avoiding a multiphcation of oints, or the forming of an ordinary knuckle joint at each end of the red.

I do not, in this application, claim specifically the rubber joint inde endently of the combination including gui ing means controllingthe joint movement as this forms the subject matter of a separate application.

What I claim as new is:-

1. A- joint comprisin an outer annular joint member, an inner oint member within the outer member, said members being subjected to forces compelling a relative movement thereof producing a limited orbital motion of the axis of one of the members at each side of the axial center of the joint about the axis of the other member; joint-connecting means adapted to provide for such orbital motion comprising a resilient rubber filler in the space between the members, said rubber filler'having a surface union with the joint members locking the surfaces of the rubber with the surfaces of the members throughout the movement of the joint.

2. A joint comprising an outer annular joint member, an inner joint member within the outer member, said. members being subjected to forces compelling a relative movement thereof producing a limited orbital motionof the. axis of one of the memhats at each side of the axial center of the joint about the axis of the other member; joint-connecting means adapted to provide for such orbital motion comprising a resilient rubber filler in the space between the members, said rubber filler being secured to the inner member by vulcanization.

3. 'oint comprising an outer annular joint member, an inner joint member within the outer member, said members being subjected to forces compelling a relative movement thereof producing a limited orbital motion of the axis of one of the members at each side of the axial center of the joint about the axis of the other member; joint-connecting means adapted toprovidefor such orbital motion comprising a resilient rubber filler in the space between the members, said rubber filler being secured to the inner and outer membersby vulcanization and being under initial tension.

' 4. A joint comprising an outer annular oint member, an inner joint member within the outer member, said members being subjected to forces compelling a combined relative oscillatory motion about and crosswise of the axes of the members, joint-connecting means adapted to provide for such oscillatory motion comprising a resilient rubber filler in the space between the members, said rubber filler having a surface union with the joint members locking the surfaces of the rubber with the surfaces of the members throughout the movement of the joint.

5. A joint comprisin an outer annular joint member, an inner oint member within the outer member, said members being subjected to forces compelling a combined relative oscillatory motion about and crosswise of the axes of the members, joint-connecting means adapted to provide for such oscillatory motion comprising a resilient rubber filler in the space between the members, said rubber filler being secured to the inner and outer members by vulcanization.

6. A joint comprising an outer annular joint member; an inner ]0int member within the outer member, said members bein subjected to forces compelling a combine relative oscillatory movement about and crosswise of the axes of the members; and jointconnecting means adapted to provide for such oscillatory motion comprislng a resilient rubber filler in the space between the members, said rubber filler being secured to the inner member by vulcanization.

In testimony whereof I have hereunto set my hand.

, HUGH C. LORD. 

